A traditional form of sample testing, in particular water testing, utilizes a vacuum filtration system to pull the sample through a membrane for further culturing and analysis. The system uses a sample container for collecting and transporting the sample to a testing site and a vacuum base that is configured to attach to a vacuum manifold source. With reference to Prior Art FIGS. 1-2, a filter membrane is removed from sterile packaging (e.g., by opening the packaging and grabbing the membrane with metal forceps that have been flamed) and is placed on the vacuum base. A vacuum funnel is clamped thereover to secure the assembly prior to vacuum filtration of the sample.
In ideal practice, the funnel and the base are autoclaved overnight prior to use (Prior Art FIG. 3). A sample bottle is taken from storage and transported to a site of interest. Some amount of sample (e.g., 250 milliliters (ml) of water) is placed in the sample container. The sample container is labeled and placed in a cooler for transport to the lab, and the sample is placed in a refrigerator at the lab until testing (Prior Art FIG. 4).
When the test environment is ready, the sample container is removed from the refrigerator (Prior Art FIG. 5). The sample container is opened, and a specified amount of sample (e.g., 100 ml) is poured into the funnel of the assembly (see Prior Art FIG. 6). The vacuum source is turned on via the manifold, and within 10 to 30 seconds, the filtrate is pulled through the membrane (Prior Art FIG. 7).
After vacuum filtration, the vacuum source is turned off, the funnel and the clamp are removed and placed aside (Prior Art FIG. 8). The forceps are flamed and extinguished. The filter is removed from the base with the forceps and placed in a Petri dish (Prior Art FIG. 9).
Subsequent to removing the filter, the filter and base are rinsed with distilled or filtered water (Prior Art FIG. 10), the funnel and base assembly are clamped together and are put in a Ultraviolet (UV) chamber for a period of time (e.g., five minutes) (Prior Art FIG. 11). The assembly is placed back on the manifold (Prior Art FIG. 12), the clamp and funnel are removed, and the base is flamed for a period of time (e.g., 10 to 15 seconds) (Prior Art FIG. 13). The interior of the funnel is also flamed for a period of time (e.g., 10 to 15 seconds) (Prior Art FIG. 14), and the assembly is clamped back together for the next sample testing (Prior Art FIG. 15).
As was noted above, the above steps are the recommended, ideal steps for ensuring that sample contamination is at a minimum. However, in practice, not all of the steps are typically performed, and sample contamination remains a problem with regard to the majority of the above iterated steps. The prior art would greatly benefit from solutions that would reduce or eliminate sample contamination with regard to one or more of the above described sample testing steps.